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Glossary of Golf Turfgrass Terms (A-C)

acid soil - A soil with a pH below the neutral point of 7.0. Soil acidity is determined by the concentration of hydrogen ions in solution. Turfgrasses generally prefer slightly acidic soils.

acid injection - Used to treat poor quality irrigation water that contains both excessive bicarbonates and a high sodium hazard. Sulfuric acid, phosphoric acid, or urea sulfuric acid is injected into the irrigation system with specialized equipment. (Also see sulfur burner).

activated sludge - A granular, porous, organic fertilizer material derived from sewerage. Aeration, digestion, and drying processes kill all bacteria and weed seeds. Nitrogen is the most valuable component of this product.

aerate - Process of aerifying soils with hollow tines, solid tines, water, or air injection: used synonymously with aerify.

air movement - Air movement across a fine turf area is important to reduce surface temperatures, dry the surface, and minimize disease activity. It usually is accomplished by pruning nearby trees and understory shrubs.

algae - A dense growth of minute, single-celled plants containing chlorophyll that develops on thin or bare areas of turf in hot, humid weather when soils are saturated with moisture.

alkaline soil - A soil having a basic reaction or a pH above the neutral point (pH 7.0); a soil having an excess of hydroxyl (OH) ions, usually found in areas of relatively low rainfall.

annual grasses - Grasses that normally complete their life cycle in one year.

approach/apron - The fairway areas in close proximity to and in front of the putting green, adjoining the putting green collar. This area is normally mowed at fairway height, but sometimes is mowed slightly closer with smaller equipment designed to preserve or improve turf quality and density.

B

bacteria - A large, widely distributed group of one-celled microorganisms, chiefly parasitic or saprophytic. Some bacteria are disease producing; many are active in processes such as fermentation, the conversion of dead organic matter into soluble food for plants, and the fixing of atmospheric nitrogen.

ball mark - A depression and/or a tear in the putting green surface made by the impact of a golf ball.

bench setting - The height at which the bedknife is set above a firm, level surface. This is generally the accepted measure for determining cutting height.

biennial - A term applied to plants that complete their life cycle in two years.

biological control - Control of turfgrass pests by the use of living organisms.

blend - A combination of two or more varieties of the same grass species.

blight - A general term used to describe symptoms of plant disease which may include sudden wilting or death of leaves, flowers, stems or entire plants.

broadleaved - Any of the dicotyledonous plants which grow in a turfgrass stand; e.g., dandelion, plantain, clover, chickweed, knotweed, etc.

brushing - In putting green maintenance, the practice of lifting excessive leaf and stem growth of grasses prior to mowing. Usually accomplished with brushes affixed ahead of the cutting reel. Topdressing brushes are often used to work sand into a putting surface.

buffer zone - An area not treated with fertilizers or pesticides, usually used as a protection zone around water features. Buffer zones provide a filtering mechanism before runoff water enters a water feature.

cation exchange capacity (CEC) - The sum total of exchangeable cations that a soil can absorb. The value represents the nutrient-holding capacity of the soil.

certified seed or plants - Usually the progeny or increases of registered or foundation stock maintained so as to preserve genetic purity. The material is inspected by a certifying agency, usually the State Crop Improvement Association.

chlorosis - The condition in plants relating to the loss or lack of green color. May be caused by disease activity, albinism, or nutritional deficiency.

clay - See 'soil separates'.

collar - An area of turf adjoining the putting surface which is mowed at a height of cut intermediate between the fairway and the putting surface. This cut is normally between 0.312 (5/16) and 0.50 (1/2) inch. The typical collar width is approximately 36 inches, but varies depending on the total green area and available mowing equipment.

combing - Using a comb, with metal teeth or flexible tines, fastened immediately in front of a reel mower for the purpose of lifting stolons and procumbent shoots so they may be cut by the mower.

compaction - State of being pressed closely together, as soil particles. Soil compaction prevents adequate water and air penetration, and reduces turfgrass HTMLContent growth.

complete fertilizer - A mixed fertilizer that contains the three major fertilizer elements; nitrogen, phosphorous, and potassium.

compost - A decomposed organic material often used as a soil additive to increase organic matter content, improve water and nutrient retention, and improve soil structure.

contour mowing - To shape the borderline between the fairway and rough to add interest, direction, or strategy to the golf hole, as in fairway contouring.

coring - A term frequently used interchangeably with aeration; the removal of a soil core from a turfgrass area as with a soil probe or hollow metal tines.

crown - The basal stem portion of the plant containing meristematic tissue. The crown is the growth point of the turf plant.

crown hydration - A term used to describe a form of winter injury in which intracellular water within the plant freezes and causes physical injury to the cell membrane and wall, resulting in dehydration.

cultivar - A group of cultivated plants that when reproduced retain their distinguishing features.

cultivation - Turfgrass cultivation is a mechanical procedure such as spiking, grooving, high pressure water injection, and deep tine, deep drill, solid tine, or hollow tine coring on established turf without destroying its sod characteristics.

cutting height - The distance above the soil line that grasses are clipped.

The actual height at which grasses are cut. Varies from bench setting, depending on the firmness of the playing surface, the degree of thatch, and flotation of cutting unit.